Apparatus for dispensing powdered material

ABSTRACT

The invention relates to an apparatus for dispensing a restricted amount of powdered material, comprising a repository ( 2 ) for powdered material ( 4 ), an outlet ( 12 ), and a conduit ( 3 ). The apparatus defines an airway arranged to enable air to be drawn through the resting powdered material in the repository, thereby entraining the powdered material in the airflow and drawing the air and entrained powdered material through the conduit. The air and entrained powdered material is thereafter expelled out of the outlet. Additionally, the invention relates to a dip tube ( 3 ) for use in apparatus for dispensing a powdered material.

[0001] The present invention relates to apparatus for dispensing arestricted or regulated amount of powdered material and component parts.Apparatus of this type are particularly useful in the delivery ofpowdered material to the human nasal tract.

[0002] The dispensing of powdered materials, both pharmaceuticallyactive and non-pharmaceutically active, is required for a number ofuses. Talcum powders are put on the skin to make it feel smooth or tohelp it stay dry. A number of anti-fungal treatments, for both plantsand animals, are dispensed in powdered form, i.e. powdered preparationsfor “athletes foot”. Powders are delivered to the lungs or nasalmembrane in the form of a spray or an aerosol for a number oftherapeutic purposes.

[0003] The topical treatment of asthma, by the application of regulatedamounts of powdered medicaments to the lungs, has become a wellestablished practice. Although not so well established, it is also knownto treat allergic rhinitis (hayfever) with powdered medicaments appliedto the nasal membranes. So treating these and similar conditions cangive rise to various advantages. Firstly, any pharmaceutically activecomponent of a powder administered in this way can take effect quicklyas, unlike with oral preparations, there is no need for it to beabsorbed via the gastro-intestinal tract before being transported to thelungs or nasal cavity. Secondly, these techniques allow ‘first-pass’effects to be avoided and, thirdly, since the powder is applied at thesite where it is required, their use reduces the systemic dosage ofactive agent (when present) and, hence, any risk of undesirable sideeffects.

[0004] As well as directly treating the epithelial cells lining the noseor lungs, powdered material can also be delivered to the nose or lungsas a means of conveying an active agent directly to the blood stream.

[0005] Powdered materials are often delivered to the lungs or nasalmembranes in the form of a spray or an aerosol produced by an inhaler orlike device. There are several main types of inhaler device currentlyavailable on the market. These include metered dose inhalers and thedevices sold under the trademarks Diskhaler® and Rotahaler®. In the caseof metered dose inhalers, the powder for delivery is contained in apressurised canister and activating a valve on the canister causes adefined amount of the powder to be released in a jet of propellant gas.Diskhalers®, on the other hand, accept magazines, each in the form of ablister pack in which each blister contains an individual doseconsisting of a defined amount of powder. To operate the device, theuser must align a loaded blister within the device, pierce it to releasethe powder and then suck the released powder into his lungs. Rotahalers®are similar, but accept single capsules of powder.

[0006] Diskhalers® and Rotahalers® require a plurality of manipulationsin order not only to load them, but also to have them release apre-measured quantity of material, before it is available for inhalationby the user. The level of manual dexterity required to use these devicesmakes them particularly unsuited to use by the very young, infirm,handicapped and old. The effective use of a metered dose inhalerrequires an ability to co-ordinate inhalation with valve actuation thatis beyond the capacity of many potential users, particularly the veryyoung.

[0007] The above discussed known devices are relatively complex piecesof apparatus, all of which include a number of intricate moving parts.This, in turn, makes them expensive to manufacture and easy to break.They are also sufficiently prone to clogging to require cleaning on adaily basis. However, they do have the advantage that they are able todispense a predetermined dose.

[0008] Although simple devices for the delivery of powdered materialexist, none are capable of restricting the level of powdered materialthat is dispensed. Such simple devices comprise a container for thepowder and an amount of the powder to be dispensed, only looselycontrolled by a simple hole, or a large gauze or open cell foam plug. Inuse, these devises are inverted and the powder allowed to freely flowdownwards, doing little to restrict the flow of the powdered material.Such devices are adequate for dispensing non-pharmaceutically activecompounds, or therapeutically active compounds with a wide therapeuticwindow, which do not require precise regulation of dosage, negating theneed to use expensive and complexes devices described. These deviceshave the advantage that they are cheap to manufacture and easy to use.However, the amount of powder dispensed is not regulated which iswasteful and therefore unduly costly.

[0009] Additionally, as these devices must be inverted for the powderedmaterial to be delivered, it is difficult to deliver the powder to theaxilla, or orifices such as the nasal cavity. Where powder is to bedelivered to the axilla, or the nasal cavity, one must adopt anuncomfortable position before inversion of the device, i.e. whendelivering powder to the nasal cavity, the head must be bend backwards.

[0010] It is an object of the present invention to provide a simpleapparatus which will regulate, to an extent, the amount of powderdelivered, which improves upon apparatus already in use.

[0011] In an embodiment of the invention a deformable bottle containssome powdered material and houses a dip tube. Squeezing the sides of thebottle, by opposing fingers, increases the internal pressure of thebottle when compared to atmospheric pressure resulting in an airflowthat is channelled out of the bottle through the dip tube. This airflowentrains the powdered material, releasing a restricted amount of thepowdered material from the bottle.

[0012] In a preferred embodiment the powder ishydroxypropylmethylcellulose, an inert cellulose powder. When deliveredinto the nasal cavity it immediately turns to a gel-like material as itreacts with the moisture present in the nasal tract. This gel is able toreplicate the properties of real mucus and as such is able to alleviate,prevent or ultimately stop a hayfever or asthma attack.

[0013] Epithelial cells lining the nasal tract contain a secretioncalled mucus, which accumulates in the cells giving them a distended andgoblet-shaped appearance. Eventually, the goblet cells burst releasingthe mucus, which as well as protecting the nasal membranes frommechanical and chemical injury also prevents inhaled particles fromreaching the delicate alveoli of the lungs.

[0014] Allergens entrained in air inhaled into the nasal tract, alighton the mucus present therein, whereby, because of the mucus's lowsurface tension, they are immediately adsorbed. The shape of the nasaltract causes a “smoke ring” effect to occur so that dust, dirt, pollenetc. is instantly separated out from and pushed to the periphery of theclear air left in the middle. This clean air is then able to enter thelungs while the mucus, which eventually drains out naturally through thedigestive system, adsorbs the allergens. People who suffer with allergicrhinitis and asthma often have a reduced amount of mucus.

[0015] The dispensing of hydroxypropylmethylcellulose to the nasalcavity, in order to mimic mucus, does not require a precise dosage asthe compound is pharmaceutically inert. However, an unrestricteddelivery of the powder may cause an uncomfortable blockage of the nasalcavity and may even result in difficulty in breathing through the nose.Furthermore, delivery of amounts of the powdered material that exceeds avolume that is required for the powder to be effective, is wasteful andtherefore unduly costly.

[0016] Accordingly, in a first aspect of the invention, there isprovided apparatus for dispensing a restricted amount of powderedmaterial, comprising a repository for powdered material, an outlet and apassageway defined between the repository and the outlet, wherein avolume of air can be propelled through powdered material resting in therepository, thereby entraining powdered material, and carry powderedmaterial thus entrained along the passageway and out of the apparatus inan upwardly direction, via the outlet.

[0017] In a preferred embodiment a restriction in the passagewayregulates the amount of powdered material delivered.

[0018] In a further preferred embodiment a conduit extends between therepository and the outlet, and defines the restriction. Preferably anentrance to the conduit is defined within the repository and saidrestriction is disposed at said entrance. More preferably, therestriction is produced by a gap defined between said entrance and awall of the repository. The conduit can comprise a tube with an open endin substantial abutment with a wall of the repository and therestriction can be provided by an opening in the wall of said tube. Theopening can be in the form of one or more notches in the open end of thetube.

[0019] It was noted during development of the apparatus in accordancewith the invention, that during manufacture of the apparatus, insertionof the dip tube resulted in the compression of the powder beneath theflat surface of the rim at the end of the dip tube, ultimately resultingin a blockage of the airway and making it difficult to fully insert thedip tube. Effective insertion of the dip tube into the apparatus wasonly capable of being effected when the apparatus was on its side.Manufacture of the apparatus in this orientation is difficult as thepowdered material may easily pour out of the apparatus, thus renderingthe manufacturing process inefficient.

[0020] Therefore, In a further embodiment the conduit comprises a tubearranged for length wise insertion into the repository and to displacepowdered material from its path transversely to said insertion.

[0021] It is preferred that the conduit comprises a tube having a wallincluding a portion with a length wise tapered cross-sectional area. Thecross-sectional perimeter of a portion of the tube can be tapered in alength wise direction. The cross-sectional area of a portion of thelumen defined by the tube can taper in a length wise direction. It ispreferred that the cross-sectional area of the tube wall tapers towardsan open end of the tube located within the repository. The open end canbe in the form of an annular knife edge. Alternatively, the tube can besealed to the repository excepting an opening, or openings, in its wall.Thus, when the conduit is forced downwards on the powdered material, thepowdered material is more easily displaced, resulting in easy insertionof the conduit when the apparatus is in the upright position.

[0022] In a preferred embodiment the apparatus is arranged for thedelivery of powdered material into a nasal cavity, this is preferablypossible wherein the outlet forms a nozzle for insertion into a nostril.

[0023] In a further preferred embodiment the conduit is a dip tube.

[0024] Apparatus in accordance with the invention may dispense powderedmaterial for the treatment of a medical condition, preferably for thetreatment of allergic rhinitis or asthma and preferably wherein thepowdered material is hydroxypropylmethylcellulose.

[0025] A further aspect of the invention is a conduit for use in theapparatus as described above.

[0026] In a yet further aspect of the present invention, there isprovided a dip tube for use in apparatus for dispensing a restrictedamount of powdered material, wherein the dip tube is arranged for lengthwise insertion into a repository and to displace is powdered materialfrom its path transversely to said insertion.

[0027] It is preferred that the dip tube comprises a tube having a wallincluding a portion with a length wise tapered cross-sectional area. Thecross-sectional perimeter of a portion of the tube can be tapered in alength wise direction. The cross-sectional area of a portion of thelumen defined by the tube can taper in a length wise direction. It ispreferred that the cross-sectional area of the tube wall tapers towardsan open end of the tube located within the repository. The open end canbe in the form of an annular knife. Alternatively, the tube can besealed to the repository excepting an opening, or openings, in its wall.

[0028] In a preferred embodiment of the invention a dip tube is arrangedfor the delivery of powdered material into a nasal cavity, this ispreferably possible wherein the outlet forms a nozzle for insertion intoa nostril.

[0029] A dip tube in accordance with the invention may dispense powderedmaterial for the treatment of a medical condition, preferably for thetreatment of allergic rhinitis or asthma wherein the powdered materialis preferably hydroxypropylmethylcellulose.

[0030] An example of an apparatus according to the present inventionwill now be described, by way of example only, and will make referenceto the following drawings.

[0031]FIG. 1 shows a side plan view (side B), and section thereof (sideA), of a nasal delivery apparatus in accordance with the invention;

[0032]FIG. 2 shows a side plan view (side A), and sectional view thereof(side B), of a dip tube in accordance with the invention;

[0033]FIG. 3 shows a side plan view (side A), and a sectional viewthereof (side B), of a dip tube in accordance with the invention;

[0034]FIG. 4 shows a side plan view (side A), and a sectional viewthereof (side B), of a dip tube in accordance with the invention.

[0035] Apparatus in accordance with the invention is shown in FIG. 1 andcomprises a cap 1 and a bottle 2, formed from a thermal plastic materialsuch as polyvinylchloride, housing a dip tube 3, and provides arepository for a quantity of powdered material 4. The cylindrical bottle2 comprises a substantially cylindrical body portion 5, extendingbetween a first end portion 6 and shoulder portion 7. The first endportion 6 defines a flat closed disc end base of the bottle 2. Thebottle also comprises a neck portion 8, extending between the shoulderportion 7 and the second end portion 12 which defines an opening. Afirst annular flange 9 extends radially outward from the neck portion 8of the cylindrical bottle 2 and is releaseably sealed with a secondannular flange 10 disposed on the cap 1, to form in use, a tamper proofsafety seal as would be readily known to a man skilled in the art. Afirst screw thread 11 commences at the first annular flange 9 andextends around and partway along the neck portion 8 of the cylindricalbottle 2 in the direction of the second end portion 12. The dip tube 3is inserted into the internal cavity 13 of the bottle 2 through theopening defined by the second end portion 12, sealing said openingdefined by the second end portion 12 by acting as a stopper for thebottle.

[0036] The dip tube 3 comprises a hollow tube with a first opening 14 atone end, opening into the internal cavity 13. The rim 15 defining thefirst opening 14 abuts with, or substantially abuts with, the internalsurface of the first end portion 6. A castellation 16 defines a notch inthe side wall of the dip tube 3, said notch defined by the castellationbeing continuous with the first opening 14. At the opposite end of thefirst opening 14 of the dip tube 3 is the second opening 17. The secondopening 17 is disposed at the tip of the nozzle portion 18 of the diptube 3. The nozzle portion 18 is a narrowed portion of the dip tube 3such that it is dimentioned to fit up a nostril. The dip tube 3 has aradial protrusion 21 which fits inside an indentation on the innersurface of the neck portion 8 of the bottle 2 to form a friction fit. Afurther radial protrusion 20 on the dip tube 3 sits on top of the bottleneck to seal the bottle.

[0037] The cap 1 is shaped such that it may releasably retain the neckportion 8 and nozzle 18 within the cavity 23 when the devise is not inuse. When not in use, first screw thread 11, co-operates with secondscrew thread 24, which is disposed on the internal surface of the cap 1.The cap 1 has a friction surface 25 extending around a portion ofexternal surface of the cap, for ease of rotation between opposingfingers during the operation of removing the cap 1 from the bottle 2.

[0038]FIG. 2 shows a preferred embodiment of the dip tube 3. Side B ofthe dotted line shows a section through the dip tube 3. The dip tube 3has a lumen 26 linking the first 14 and second 17 openings. The innerwall 27 and outer wall 28 become gradually closer, graduations occur inthe portion of the dip tube 3 that is disposed within the body portion 5of the bottle 2. This narrowing of the width of the wall results in agradual reduction in the diameter of the dip tube 2 and an increase inthe diameter of the lumen 26 within the dip tube 2. The narrowest pointof the tapering portion 22 defines the first opening 14. At this pointthe inner wall and the outer wall meet to form the rim 15 of the firstopening 14. The sectional profile of the rim 15 being rounded.

[0039] In an alternative embodiment as shown in FIG. 3 the inner andouter walls taper to the first opening 14 with an inner wall 27 andouter wall 28 meeting to form a sharp point at the rim 15 in sectionedprofile.

[0040] In a further alternative embodiment, as shown in FIG. 4, the endof the tip tube 3, to be located in the internal cavity 13, is formed asif cut at an acute angle to the tube's axis and sealed with an elipticalend plate 29. A first opening 14 is formed in the side wall of the diptube 3 adjacent to the plate 29.

[0041] In use, the cylindrical bottle 2 is filled with powered material4. A user should place the nozzle 18 defining the second end portion 12of the dip tube 3 into a nostril and then squeeze the body portion 5between opposing fingers. The compression of the body portion 5 reducesthe volume of the cylindrical bottle 2, thereby increasing internalpressure relative to atmospheric pressure. This results in a proportionof the air within the cylindrical bottle flowing down the pressuregradient and finding an exit by travelling through the castellation 16,up through the lumen 26 of the dip tube 3 and exiting at the secondopening 17 into the nostril. As the air flows through the apparatus,particles of the powered material 4 will become entrained therein. Thelimited volume of the powder 4 that is capable of passage throughcastellation 16 whilst entrained in the air flow will be delivered tothe nasal cavity. The pressure gradient will be transient, asequilibrium will be re-established rapidly. The transience of the airflow combined with the fact that the castellation 16 limits the amountof powered material 4 that is given passage to the lumen 26, results ina regulation of the powered material 4 that is capable of expulsion fromthe apparatus during a single compression of the body portion 5.

1. Apparatus for dispensing a restricted amount of powdered material,comprising a repository for powdered material, an outlet and apassageway defined between the repository and the outlet, wherein avolume of air can be propelled through powdered material resting in therepository, thereby entraining powdered material, and carry powderedmaterial thus entrained along the passageway and out of the apparatus inan upwardly direction, via the outlet.
 2. Apparatus as claimed claim 1,wherein a restriction in the passageway regulates the amount of powderedmaterial delivered.
 3. Apparatus as claimed in claim 2, wherein aconduit extends between the repository and the outlet, and defines therestriction.
 4. Apparatus as claimed in claim 3, wherein an entrance tothe conduit is defined within the repository and said restriction isdisposed at said entrance.
 5. Apparatus as claimed in claim 4, whereinthe restriction is produced by a gap defined between said entrance and awall of the repository.
 6. Apparatus as claimed in claim 5, wherein theconduit comprises a tube with an open end in substantial abutment with awall of the repository and the restriction is provided by an opening inthe wall of said tube.
 7. Apparatus as claimed in any of claims 3 to 6,wherein said opening is in the form of one or more notches in the openend of the tube.
 8. Apparatus as claimed in any of claims 3 to 7,wherein the conduit comprises a tube arranged for length wise insertioninto the repository and to displace powdered material from its pathtransversely to said insertion.
 9. Apparatus as claimed in any of claims4 to 8, wherein the conduit comprises a tube having a wall including aportion with a length wise tapered cross-sectional area.
 10. Apparatusas claimed in claim 8 or 9, wherein the cross-sectional perimeter of aportion of the tube is tapered in a length wise direction.
 11. Apparatusas claimed in claim 9, wherein the cross-sectional area of a portion ofthe lumen defined by the tube tapers in a length wise direction. 12.Apparatus as claimed in any of claims 9 to 11, wherein thecross-sectional area of the tube wall tapers towards an open end of thetube located within the repository.
 13. Apparatus as claimed in claim12, wherein said open end is in the form of an annular knife edge. 14.Apparatus as claimed in claim 10, wherein the tube is sealed to therepository excepting an opening, or openings, in its wall.
 15. Apparatusas claimed in any of the preceding claims, arranged for the delivery ofpowdered material into a nasal cavity.
 16. Apparatus as claimed in claim15, wherein the outlet forms a nozzle for insertion into a nostril. 17.Apparatus as claimed in any of the preceding claims, where the conduitis a dip tube.
 18. Apparatus as claimed in all preceding claims whereinthe powdered material is for the treatment of a medical condition. 19.Apparatus as claimed in claim 18, wherein the powdered material is forthe treatment of allergic rhinitis or asthma.
 20. Apparatus as claimedin claim 18 or 19, wherein the powdered material ishydroxypropylmethylcellulose.
 21. A conduit for use in the apparatus asclaimed in any of the preceding claims.
 22. A dip tube for use inapparatus for dispensing a restricted amount of powdered material,wherein the dip tube is arranged for length wise insertion into arepository and to displace powdered material from its path transverselyto said insertion.
 23. A dip tube as claimed in claim 22, wherein thedip tube comprises a tube having a wall including a portion with alength wise tapered cross-sectional area.
 24. A dip tube as claimed inclaim 22 or 23, wherein the cross-sectional perimeter of a portion ofthe tube is tapered in a length wise direction.
 25. A dip tube asclaimed in claim 23, wherein the cross-sectional area of a portion ofthe lumen defined by the tube tapers in a length wise direction.
 26. Adip tube as claimed in any of claims 23-25, wherein the cross-sectionalarea of the tube wall tapers towards an open end of the tube locatedwithin the repository.
 27. A dip tube as claimed in claim 26, whereinsaid open end is in the form of an annular knife edge.
 28. A dip tube asclaimed in claim 24, wherein the tube is sealed to the repositoryexcepting an opening, or openings, in its wall.
 29. A dip tube asclaimed in any of claims 22 to 28, arranged for the delivery of powderedmaterial into a nasal cavity.
 30. A dip tube as claimed in claim 29,wherein the outlet forms a nozzle for insertion into a nostril.
 31. Adip tube as claimed in any of claims 22 to 30, wherein the powderedmaterial is for the treatment of a medical condition.
 32. A dip tube asclaimed in claim 31, wherein the powdered material is for the treatmentof allergic rhinitis or asthma.
 33. A dip tube as claimed in any ofclaims 31 or 32, wherein the powdered material ishydroxypropylmethylcellulose.
 34. Apparatus substantially ashereinbefore described with reference to the figures.
 35. A dip tubesubstantially as hereinbefore described with reference to the figures.